Artículos de revistas: "RF-EMF Exposure"

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Zeleke, Berihun M., Christopher Brzozek, Chhavi R. Bhatt, Michael J. Abramson, Frederik Freudenstein, Rodney J. Croft, Peter Wiedemann y Geza Benke. "Wi-fi related radiofrequency electromagnetic fields (RF-EMF): a pilot experimental study of personal exposure and risk perception". Journal of Environmental Health Science and Engineering 19, n.º 1 (23 de marzo de 2021): 671–80. http://dx.doi.org/10.1007/s40201-021-00636-7.

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AbstractThe impact of providing people with an objectively measured personal radiofrequency electromagnetic fields (RF-EMF) exposure information on the risk perception of people is not well understood. We conducted an experimental study, among three groups of participants, to investigate the risk perception of people towards RF-EMF from Wi-Fi sources (ISM 2.4 GHz) by providing participants with either basic text, precautionary information, or a summary of their personal RF-EMF exposure measurement levels. Participants provided with personal RF-EMF exposure measurement information were more confident in protecting themselves from RF-EMF exposure, compared to those provided with only basic information. Nonetheless, neither the exposure perception nor the risk perception of people to Wi-Fi related RF-EMF differed by the type of information provided. The measured Wi-Fi signal levels were far below international exposure limits. Furthermore, self-rated levels of personal RF-EMF exposure perception were not associated with objectively measured RF-EMF exposure levels. Providing people with objectively measured information may help them build confidence in protecting themselves from Wi-Fi related RF-EMF exposure.

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Goh, Jaeseong, Dongwha Suh, Gyuyeon Park, Sangbong Jeon, Youngseung Lee, Nam Kim y Kiwon Song. "1.7 GHz long-term evolution radiofrequency electromagnetic field with stable power monitoring and efficient thermal control has no effect on the proliferation of various human cell types". PLOS ONE 19, n.º 5 (7 de mayo de 2024): e0302936. http://dx.doi.org/10.1371/journal.pone.0302936.

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Long-term evolution (LTE) radiofrequency electromagnetic field (RF-EMF) is widely used in communication technologies. Thus, the influence of RF-EMF on biological systems is a major public concern and its physiological effects remain controversial. In our previous study, we showed that continuous exposure of various human cell types to 1.7 GHz LTE RF-EMF at a specific absorption rate (SAR) of 2 W/Kg for 72 h can induce cellular senescence. To understand the precise cellular effects of LTE RF-EMF, we elaborated the 1.7 GHz RF-EMF cell exposure system used in the previous study by replacing the RF signal generator and developing a software-based feedback system to improve the exposure power stability. This refinement of the 1.7 GHz LTE RF-EMF generator facilitated the automatic regulation of RF-EMF exposure, maintaining target power levels within a 3% range and a constant temperature even during the 72-h-exposure period. With the improved experimental setup, we examined the effect of continuous exposure to 1.7 GHz LTE RF-EMF at up to SAR of 8 W/Kg in human adipose tissue-derived stem cells (ASCs), Huh7, HeLa, and rat B103 cells. Surprisingly, the proliferation of all cell types, which displayed different growth rates, did not change significantly compared with that of the unexposed controls. Also, neither DNA damage nor cell cycle perturbation was observed in the 1.7 GHz LTE RF-EMF-exposed cells. However, when the thermal control system was turned off and the subsequent temperature increase induced by the RF-EMF was not controlled during continuous exposure to SAR of 8 W/Kg LTE RF-EMF, cellular proliferation increased by 35.2% at the maximum. These observations strongly suggest that the cellular effects attributed to 1.7 GHz LTE RF-EMF exposure are primarily due to the induced thermal changes rather than the RF-EMF exposure itself.

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Zeleke, Berihun, Christopher Brzozek, Chhavi Bhatt, Michael Abramson, Rodney Croft, Frederik Freudenstein, Peter Wiedemann y Geza Benke. "Personal Exposure to Radio Frequency Electromagnetic Fields among Australian Adults". International Journal of Environmental Research and Public Health 15, n.º 10 (12 de octubre de 2018): 2234. http://dx.doi.org/10.3390/ijerph15102234.

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The measurement of personal exposure to radiofrequency electromagnetic fields (RF-EMFs) is important for epidemiological studies. RF-EMF exposure can be measured using personal exposimeters that register RF-EMFs over a wide range of frequency bands. This study aimed to measure and describe personal RF-EMF exposure levels from a wide range of frequency bands. Measurements were recorded from 63 participants over an average of 27.4 (±4.5) hours. RF-EMF exposure levels were computed for each frequency band, as well as from downlink (RF from mobile phone base station), uplink (RF from mobile phone handsets), broadcast, and Wi-Fi. Participants had a mean (±SD) age of 36.9 ± 12.5 years; 66.7% were women; and almost all (98.2%) from urban areas. A Wi-Fi router at home was reported by 61 participants (96.8%), with 38 (61.2%) having a Wi-Fi enabled smart TV. Overall, 26 (41.3%) participants had noticed the existence of a mobile phone base station in their neighborhood. On average, participants estimated the distance between the base station and their usual residence to be about 500 m. The median personal RF-EMF exposure was 208 mV/m. Downlink contributed 40.4% of the total RF-EMF exposure, followed by broadcast (22.4%), uplink (17.3%), and Wi-Fi (15.9%). RF-EMF exposure levels on weekdays were higher than weekends (p < 0.05). Downlink and broadcast are the main contributors to total RF-EMF personal exposure. Personal RF-EMF exposure levels vary according to day of the week and time of day.

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Kim, Ju Hwan, Kyung Hwun Chung, Yeong Ran Hwang, Hye Ran Park, Hee Jung Kim, Hyung-Gun Kim y Hak Rim Kim. "Exposure to RF-EMF Alters Postsynaptic Structure and Hinders Neurite Outgrowth in Developing Hippocampal Neurons of Early Postnatal Mice". International Journal of Molecular Sciences 22, n.º 10 (19 de mayo de 2021): 5340. http://dx.doi.org/10.3390/ijms22105340.

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Exposure to radiofrequency electromagnetic fields (RF-EMFs) has increased rapidly in children, but information on the effects of RF-EMF exposure to the central nervous system in children is limited. In this study, pups and dams were exposed to whole-body RF-EMF at 4.0 W/kg specific absorption rate (SAR) for 5 h per day for 4 weeks (from postnatal day (P) 1 to P28). The effects of RF-EMF exposure on neurons were evaluated by using both pups’ hippocampus and primary cultured hippocampal neurons. The total number of dendritic spines showed statistically significant decreases in the dentate gyrus (DG) but was not altered in the cornu ammonis (CA1) in hippocampal neurons. In particular, the number of mushroom-type dendritic spines showed statistically significant decreases in the CA1 and DG. The expression of glutamate receptors was decreased in mushroom-type dendritic spines in the CA1 and DG of hippocampal neurons following RF-EMF exposure. The expression of brain-derived neurotrophic factor (BDNF) in the CA1 and DG was significantly lower statistically in RF-EMF-exposed mice. The number of post-synaptic density protein 95 (PSD95) puncta gradually increased over time but was significantly decreased statistically at days in vitro (DIV) 5, 7, and 9 following RF-EMF exposure. Decreased BDNF expression was restricted to the soma and was not observed in neurites of hippocampal neurons following RF-EMF exposure. The length of neurite outgrowth and number of branches showed statistically significant decreases, but no changes in the soma size of hippocampal neurons were observed. Further, the memory index showed statistically significant decreases in RF-EMF-exposed mice, suggesting that decreased synaptic density following RF-EMF exposure at early developmental stages may affect memory function. Collectively, these data suggest that hindered neuronal outgrowth following RF-EMF exposure may decrease overall synaptic density during early neurite development of hippocampal neurons.

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Chiaramello, Emma, Marta Bonato, Serena Fiocchi, Gabriella Tognola, Marta Parazzini, Paolo Ravazzani y Joe Wiart. "Radio Frequency Electromagnetic Fields Exposure Assessment in Indoor Environments: A Review". International Journal of Environmental Research and Public Health 16, n.º 6 (17 de marzo de 2019): 955. http://dx.doi.org/10.3390/ijerph16060955.

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Exposure to radiofrequency (RF) electromagnetic fields (EMFs) in indoor environments depends on both outdoor sources such as radio, television and mobile phone antennas and indoor sources, such as mobile phones and wireless communications applications. Establishing the levels of exposure could be challenging due to differences in the approaches used in different studies. The goal of this study is to present an overview of the last ten years research efforts about RF EMF exposure in indoor environments, considering different RF-EMF sources found to cause exposure in indoor environments, different indoor environments and different approaches used to assess the exposure. The highest maximum mean levels of the exposure considering the whole RF-EMF frequency band was found in offices (1.14 V/m) and in public transports (0.97 V/m), while the lowest levels of exposure were observed in homes and apartments, with mean values in the range 0.13–0.43 V/m. The contribution of different RF-EMF sources to the total level of exposure was found to show slightly different patterns among the indoor environments, but this finding has to be considered as a time-dependent picture of the continuous evolving exposure to RF-EMF.

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Vilić, Marinko, Ivona Žura Žaja, Mirta Tkalec, Anamaria Štambuk, Maja Šrut, Goran Klobučar, Krešimir Malarić, Perica Tucak, Selim Pašić y Ivana Tlak Gajger. "Effects of a radio frequency electromagnetic field on honey bee larvae (Apis mellifera) differ in relation to the experimental study design". Veterinarski arhiv 91, n.º 4 (15 de septiembre de 2021): 427–35. http://dx.doi.org/10.24099/vet.arhiv.1321.

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Exposure to radiofrequency electromagnetic fields (RF-EMF) at the operating frequencies of different communication devices can cause various biological effects. However, there is a lack of studies on the oxidative stress response and genotoxicity in the honey bee (Apis mellifera) after exposure to RF-EMF. In this study, we investigated the oxidative stress and DNA damage in honey bee larvae situated in waxcomb cells, exposed to modulated RF-EMF 23 Vm-1. The glutathione S-transferase activity decreased, whereas the catalase activity increased significantly in the honey bee larvae upon RF-EMF exposure. Superoxide dismutase activity, the level of lipid peroxidation, and DNA damage were not statistically altered in exposed honey bee larvae when compared to the control group. These results suggest that the biological effects of modulated RF-EMF in honey bee larvae depend on the exposure design.

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Freudenstein, Frederik, Peter M. Wiedemann y Tim W. C. Brown. "Exposure Perception as a Key Indicator of Risk Perception and Acceptance of Sources of Radio Frequency Electromagnetic Fields". Journal of Environmental and Public Health 2015 (2015): 1–9. http://dx.doi.org/10.1155/2015/198272.

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The presented survey was conducted in six European countries as an online study. A total of 2454 subjects participated. Two main research questions were investigated: firstly, how does the cognitive, moral, and affective framing of radio frequency electromagnetic field (RF EMF) exposure perception influence RF EMF risk perception? Secondly, can the deployment of mobile phone base stations have greater acceptance with RF EMF exposure reduction? The findings with respect to the first question clearly indicated that the cognitive framed exposure perception is the main determinant of RF EMF risk perception. The concomitant sensitivity to exposure strength offers an opportunity to improve the acceptance of base stations by exposure reduction. A linear regression analysis supported this assumption: in a fictional test situation, exposure reduction improved the acceptance of base stations, operationalized as the requested distance of the base station from one’s own home. Furthermore, subjects with high RF EMF risk perception were most sensitive to exposure reduction. On average, a 70% exposure reduction reduced the requested distance from about 2000 meters to 1000 meters. The consequences for risk communication are discussed.

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Alexias, Aris, Yiannis Kiouvrekis, Vasiliki Softa, Constantin Kappas, Charilaos Tyrakis y Kiki Theodorou. "RF-EMF EXPOSURE LEVELS IN SENSITIVE LAND USE IN GREECE: EDUCATIONAL UNITS CENSUS IN THE MUNICIPALITY OF KORYDALLOS". Radiation Protection Dosimetry 190, n.º 2 (junio de 2020): 193–99. http://dx.doi.org/10.1093/rpd/ncaa090.

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Abstract Background The growing popularity of mobile phones and the expansion of network infrastructure in Greece have raised concerns about the possible negative health effects on sensitive groups, such as children, from exposure to long-term radiofrequency electromagnetic fields (RF-EMFs). Aims The objective of this study is to estimate mean RF-EMF exposure levels of primary and secondary education schools located in the municipality of Korydallos, Athens, Greece. Methods We performed measurements to all the schools units ($n=62$) in the region in order to calculate the mean value for RF-EMF exposure in the range of 27 MHz–3 GHz, which covers the whole spectrum of RF-EMF sources. Results At the $97.5\%$ of schools found in Korydallos region, the exposure level is at least 2200 times below the Greek exposure limits. Conclusion The exposure levels in the locations tested are both below $60\%$ of the highest limit set by the International Commission on Non-Ionizing Radiation Protection regarding school exposures.

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Veerana, Mayura, Nan-Nan Yu, Si-Jin Bae, Ikhwan Kim, Eun-Seong Kim, Wirinthip Ketya, Hak-Yong Lee, Nam-Young Kim y Gyungsoon Park. "Enhancement of Fungal Enzyme Production by Radio-Frequency Electromagnetic Fields". Journal of Fungi 8, n.º 11 (10 de noviembre de 2022): 1187. http://dx.doi.org/10.3390/jof8111187.

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Enzyme production by microorganisms on an industrial scale has demonstrated technical bottlenecks, such as low efficiency in enzyme expression and extracellular secretion. In this study, as a potential tool for overcoming these technical limits, radio-frequency electromagnetic field (RF-EMF) exposure was examined for its possibility to enhance production of an enzyme, α-amylase, in a filamentous fungus, Aspergillus oryzae. The RF-EMF perfectly resonated at 2 GHz with directivity radiation pattern and peak gain of 0.5 dB (0.01 Watt). Total protein concentration and activity of α-amylase measured in media were about 1.5–3-fold higher in the RF-EMF exposed (10 min) sample than control (no RF-EMF) during incubation (the highest increase after 16 h). The level of α-amylase mRNA in cells was approximately 2–8-fold increased 16 and 24 h after RF-EMF exposure for 10 min. An increase in vesicle accumulation within fungal hyphae and the transcription of some genes involved in protein cellular trafficking was observed in RF-EMF-exposed samples. Membrane potential was not changed, but the intracellular Ca2+ level was elevated after RF-EMF exposure. Our results suggest that RF-EMF can increase the extracellular level of fungal total proteins and α-amylase activity and the intracellular level of Ca2+.

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Vargová, Blažena, Juraj Kurimský, Roman Cimbala, Michal Kosterec, Igor Majláth, Natália Pipová, Piotr Tryjanowski, Łukasz Jankowiak y Viktoria Majlathova. "Ticks and radio-frequency signals: behavioural response of ticks (Dermacentor reticulatus) in a 900 MHz electromagnetic field". Systematic and Applied Acarology 22, n.º 5 (5 de mayo de 2017): 683. http://dx.doi.org/10.11158/saa.22.5.7.

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The electromagnetic field (EMF) is present in the environment throughout the world and encompasses both natural and human-made sources of electromagnetic fields. It has been shown that EMF influences a variety of biological systems, including the behavioural responses of both vertebrates and invertebrates. As such, determining the effects of the EMF on the ecosystem in detail may be important for understanding the ecology and biology of organisms, particularly those, such as ticks, that are important in disease transmission. Our main goal was to determine if the tick, Dermacentor reticulatus, interacts with the EMF. An experimental behavioural test of tick sensitivity to radio frequency power radiation was performed under laboratory conditions. Tests were performed in an electromagnetic compatibility laboratory in a radio frequency electromagnetic field (RF-EMF) anechoic chamber. Ticks were irradiated using a Double-Ridged Waveguide Horn Antenna with 900 MHz RF-EMF. The applied radio-frequency power was tuned below the proposed limit for public exposure to mobile phone base stations. We found that exposure induces an immediate tick locomotor response manifested either in a previously unreported jerking movement of the whole body or in jerking of the first pair of legs. Overall, ticks exhibited significantly greater movement in the presence of the RF-EMF. Significant sex differences relative to RF-EMF exposure were observed in both response variables. In the presence of RF-EMF, body jerking by females was greater than in males and vice versa for leg jerks. This study represents the first experimental evidence of a behavioural response of D. reticulatus ticks to exposure to RF-EMF.

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Park, Jeongyeon, Jong Hwa Kwon, Nam Kim y Kiwon Song. "Effects of 1950 MHz radiofrequency electromagnetic fields on Aβ processing in human neuroblastoma and mouse hippocampal neuronal cells". Journal of Radiation Research 59, n.º 1 (6 de octubre de 2017): 18–26. http://dx.doi.org/10.1093/jrr/rrx045.

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Abstract Alzheimer’s disease (AD) is a neurodegenerative disease leading to progressive loss of memory and other cognitive functions. One of the well-known pathological markers of AD is the accumulation of amyloid-beta protein (Aβ), and its plaques, in the brain. Recent studies using Tg-5XFAD mice as a model of AD have reported that exposure to radiofrequency electromagnetic fields (RF-EMF) from cellular phones reduced Aβ plaques in the brain and showed beneficial effects on AD. In this study, we examined whether exposure to 1950 MHz RF-EMF affects Aβ processing in neural cells. We exposed HT22 mouse hippocampal neuronal cells and SH-SY5Y human neuroblastoma cells to RF-EMF (SAR 6 W/kg) for 2 h per day for 3 days, and analyzed the mRNA and protein expression of the key genes related to Aβ processing. When exposed to RF-EMF, mRNA levels of APP, BACE1, ADAM10 and PSEN1 were decreased in HT22, but the mRNA level of APP was not changed in SH-SY5Y cells. The protein expression of APP and BACE1, as well as the secreted Aβ peptide, was not significantly different between RF-EMF–exposed 7w-PSML, HT22 and SH-SY5Y cells and the unexposed controls. These observations suggest that RF-EMF exposure may not have a significant physiological effect on Aβ processing of neural cells in the short term. However, considering that we only exposed HT22 and SH-SY5Y cells to RF-EMF for 2 h per day for 3 days, we cannot exclude the possibility that 1950 MHz RF-EMF induces physiological change in Aβ processing with long-term and continuous exposure.

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Tran, Nam Trung, Luca Jokic, Julian Keller, Jens Uwe Geier y Ralf Kaldenhoff. "Impacts of Radio-Frequency Electromagnetic Field (RF-EMF) on Lettuce (Lactuca sativa)—Evidence for RF-EMF Interference with Plant Stress Responses". Plants 12, n.º 5 (28 de febrero de 2023): 1082. http://dx.doi.org/10.3390/plants12051082.

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The increased use of wireless technology causes a significant exposure increase for all living organisms to radio frequency electromagnetic fields (RF-EMF). This comprises bacteria, animals, and also plants. Unfortunately, our understanding of how RF-EMF influences plants and plant physiology remains inadequate. In this study, we examined the effects of RF-EMF radiation on lettuce plants (Lactuca sativa) in both indoor and outdoor environments using the frequency ranges of 1890–1900 MHz (DECT) at 2.4 GHz and 5 GHz (Wi-Fi). Under greenhouse conditions, RF-EMF exposure had only a minor impact on fast chlorophyll fluorescence kinetics and no effect on plant flowering time. In contrast, lettuce plants exposed to RF-EMF in the field showed a significant and systemic decrease in photosynthetic efficiency and accelerated flowering time compared to the control groups. Gene expression analysis revealed significant down-regulation of two stress-related genes in RF-EMF-exposed plants: violaxanthin de-epoxidase (VDE) and zeaxanthin epoxidase (ZEP). RF-EMF-exposed plants had lower Photosystem II’s maximal photochemical quantum yield (FV/FM) and non-photochemical quenching (NPQ) than control plants under light stress conditions. In summary, our results imply that RF-EMF might interfere with plant stress responses and reduced plant stress tolerance.

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Mulugeta, Biruk Ashenafi, Shanshan Wang, Wassim Ben Chikha, Jiang Liu, Christophe Roblin y Joe Wiart. "Statistical Characterization and Modeling of Indoor RF-EMF Down-Link Exposure". Sensors 23, n.º 7 (29 de marzo de 2023): 3583. http://dx.doi.org/10.3390/s23073583.

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With the increasing use of wireless communication systems, assessment of exposure to radio-frequency electromagnetic field (RF-EMF) has now become very important due to the rise of public risk perception. Since people spend more than 70% of their daily time in indoor environments, including home, office, and car, the efforts devoted to indoor RF-EMF exposure assessment has also increased. However, assessment of indoor exposure to RF-EMF using a deterministic approach is challenging and time consuming task as it is affected by uncertainties due to the complexity of the indoor environment and furniture structure, existence of multiple reflection, refraction, diffraction and scattering, temporal variability of exposure, and existence of many obstructions with unknown dielectric properties. Moreover, it is also affected by the existence of uncontrolled factors that can influence the indoor RF-EMF exposure such as the constant movement of people and random movement of furniture and doors as people are working in the building. In this study, a statistical approach is utilized to characterize and model the total indoor RF-EMF down-link (DL) exposure from all cellular bands on each floor over the length of a wing since the significance of distance is very low between any two points on each floor in a wing and the variation of RF-EMF DL exposure is mainly influenced by the local indoor environment. Measurements were conducted in three buildings that are located within a few hundred meters vicinity of two base station sites supporting several cellular technologies (2G, 3G, 4G, and 5G). We apply the one-sample Kolmogorov–Smirnov test on the measurement data, and we prove that the indoor RF-EMF DL exposure on each floor over the length of a wing is a random process governed by a Gaussian distribution. We validate this proposition using leave-one-out cross validation technique. Consequently, we conclude that the indoor RF-EMF DL exposure on each floor over the length of a wing can be modeled by a Gaussian distribution and, therefore, can be characterized by the mean and the standard deviation parameters.

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Olejárová, Soňa, Roman Moravčík y Iveta Herichová. "2.4 GHz Electromagnetic Field Influences the Response of the Circadian Oscillator in the Colorectal Cancer Cell Line DLD1 to miR-34a-Mediated Regulation". International Journal of Molecular Sciences 23, n.º 21 (30 de octubre de 2022): 13210. http://dx.doi.org/10.3390/ijms232113210.

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Radiofrequency electromagnetic fields (RF-EMF) exert pleiotropic effects on biological processes including circadian rhythms. miR-34a is a small non-coding RNA whose expression is modulated by RF-EMF and has the capacity to regulate clock gene expression. However, interference between RF-EMF and miR-34a-mediated regulation of the circadian oscillator has not yet been elucidated. Therefore, the present study was designed to reveal if 24 h exposure to 2.4 GHz RF-EMF influences miR-34a-induced changes in clock gene expression, migration and proliferation in colorectal cancer cell line DLD1. The effect of up- or downregulation of miR-34a on DLD1 cells was evaluated using real-time PCR, the scratch assay test and the MTS test. Administration of miR-34a decreased the expression of per2, bmal1, sirtuin1 and survivin and inhibited proliferation and migration of DLD1 cells. When miR-34a-transfected DLD1 cells were exposed to 2.4 GHz RF-EMF, an increase in cry1 mRNA expression was observed. The inhibitory effect of miR-34a on per2 and survivin was weakened and abolished, respectively. The effect of miR-34a on proliferation and migration was eliminated by RF-EMF exposure. In conclusion, RF-EMF strongly influenced regulation mediated by the tumour suppressor miR-34a on the peripheral circadian oscillator in DLD1 cells.

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Sousa, Micelange Carvalho, Frederico Costa, Pablo Diego Lima, Yone De Camargo Setogute, Brenda Pires Gumz, Fernanda Azevedo, Jorge Sabbaga et al. "Low energy amplitude modulated radiofrequency electromagnetic fields in combination with standard treatment or as monotherapy to show improvement in quality of life in patients with advanced hepatocellular carcinoma." Journal of Clinical Oncology 39, n.º 3_suppl (20 de enero de 2021): 290. http://dx.doi.org/10.1200/jco.2021.39.3_suppl.290.

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290 Background: Hepatocellular carcinoma (HCC) is a fatal cancer without curative option for most patients. Hence the importance to improve health related quality of life (HRQoL). Amplitude-modulated radiofrequency electromagnetic fields (EMF), as a novel and non-toxic therapy, has potential for improving HRQoL in advanced HCC patients. Methods: An open-label, single center, prospective clinical protocol was performed in advanced HCC patients as an initial and salvage treatment modality. Systemic exposure to EMF was used in combination with a systemic conventional treatment or as a single treatment. A spoon-shaped antenna placed in the oral cavity delivered EMF over 90 minutes with monthly repetitions until death or consent withdrawal. The effect on HRQoL was the primary objective of this study. Patients answered the EORTC-C30 v3.0 questionnaires prior to every EMF exposure. Clinically meaningful change (CMC) and time to deterioration (TTD) for Global Health (QoL), Role Functioning (RF) and Physical Functioning (PF) were used in the analysis. Results: From March 2018 to April 2020, 55 advanced HCC patients were submitted to 373 EMF exposures. 41/55 (75%) patients had repetitive exposures (mean # 4, ranging from 2-16). 87% were male, median age was 67, 84% were BLCL-C, 16% were Child-Pugh B, 29% had extra-hepatic metastasis, 55% had failed previous treatment and 71% had documented radiological progression. 31(56%) patients received EMF in combination with systemic therapy (28 TKI and 3 anti-PDL1). 24 patients received EMF as a single treatment modality. The mean baseline score was 68.1 for QoL and 77.1 for RF and PF. 61%, 76% and 49% of patients experienced positive change in QoL, RF and PS scores immediately prior to the second exposure, respectively. +CMC was reported in 20%, 17% and 32% of patients, respectively for QoL, RF and PS. The median QoL TTD was not reached. The median RF TTD was 7.2 month and the median PF TTD was 11.9 month. The median RF TTD for patients in combination treatment was 11.4 months and in a single treatment was 13.5 month. The median PF TTD for patients in combination treatment was 12.8 months and in single treatment was 14.5 month. Conclusions: Advanced HCC patients showed positive changes in QoL, RF and PF HRQoL scores after single exposure to EMF. The benefit from EMF in HRQoL was durable both in combination with TKI or as a single modality in advanced HCC patients. These results support future development as a novel palliative treatment modality in advanced HCC patients. Clinical trial information: NCT 01686412.

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Benini, Martina, Marta Parazzini, Marta Bonato, Silvia Gallucci, Emma Chiaramello, Serena Fiocchi y Gabriella Tognola. "Road User Exposure from ITS-5.9 GHz Vehicular Connectivity". Sensors 22, n.º 18 (15 de septiembre de 2022): 6986. http://dx.doi.org/10.3390/s22186986.

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This study addressed an important but not yet thoroughly investigated topic regarding human exposure to radio-frequency electromagnetic fields (RF-EMF) generated by vehicular connectivity. In particular, the study assessed, by means of computational dosimetry, the RF-EMF exposure in road users near a car equipped with vehicle-to-vehicle (V2V) communication antennas. The exposure scenario consisted of a 3D numerical model of a car with two V2V antennas, each fed with 1 W, operating at 5.9 GHz and an adult human model to simulate the road user near the car. The RF-EMF dose absorbed by the human model was calculated as the specific absorption rate (SAR), that is, the RF-EMF power absorbed per unit of mass. The highest SAR was observed in the skin of the head (34.7 mW/kg) and in the eyes (15 mW/kg); the SAR at the torso (including the genitals) and limbs was negligible or much lower than in the head and eyes. The SAR over the whole body was 0.19 mW/kg. The SAR was always well below the limits of human exposure in the 100 kHz–6 GHz band established by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The proposed approach can be generalized to assess RF-EMF exposure in different conditions by varying the montage/number of V2V antennas and considering human models of different ages.

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Kim, Ju Hwan, Da-Hyeon Yu, Hyo-Jeong Kim, Yang Hoon Huh, Seong-Wan Cho, Jin-Koo Lee, Hyung-Gun Kim y Hak Rim Kim. "Exposure to 835 MHz radiofrequency electromagnetic field induces autophagy in hippocampus but not in brain stem of mice". Toxicology and Industrial Health 34, n.º 1 (22 de noviembre de 2017): 23–35. http://dx.doi.org/10.1177/0748233717740066.

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The exploding popularity of mobile phones and their close proximity to the brain when in use has raised public concern regarding possible adverse effects from exposure to radiofrequency electromagnetic fields (RF-EMF) on the central nervous system. Numerous studies have suggested that RF-EMF emitted by mobile phones can influence neuronal functions in the brain. Currently, there is still very limited information on what biological mechanisms influence neuronal cells of the brain. In the present study, we explored whether autophagy is triggered in the hippocampus or brain stem after RF-EMF exposure. C57BL/6 mice were exposed to 835 MHz RF-EMF with specific absorption rates (SAR) of 4.0 W/kg for 12 weeks; afterward, the hippocampus and brain stem of mice were dissected and analyzed. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis demonstrated that several autophagic genes, which play key roles in autophagy regulation, were significantly upregulated only in the hippocampus and not in the brain stem. Expression levels of LC3B-II protein and p62, crucial autophagic regulatory proteins, were significantly changed only in the hippocampus. In parallel, transmission electron microscopy (TEM) revealed an increase in the number of autophagosomes and autolysosomes in the hippocampal neurons of RF-EMF-exposed mice. The present study revealed that autophagy was induced in the hippocampus, not in the brain stem, in 835 MHz RF-EMF with an SAR of 4.0 W/kg for 12 weeks. These results could suggest that among the various adaptation processes to the RF-EMF exposure environment, autophagic degradation is one possible mechanism in specific brain regions.

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Loughran, Verrender, Dalecki, Burdon, Tagami, Park, Taylor y Croft. "Radiofrequency Electromagnetic Field Exposure and the Resting EEG: Exploring the Thermal Mechanism Hypothesis". International Journal of Environmental Research and Public Health 16, n.º 9 (28 de abril de 2019): 1505. http://dx.doi.org/10.3390/ijerph16091505.

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There is now strong evidence that radiofrequency electromagnetic field (RF-EMF) exposure influences the human electroencephalogram (EEG). While effects on the alpha band of the resting EEG have been repeatedly shown, the mechanisms underlying that effect have not been established. The current study used well-controlled methods to assess the RF-EMF exposure effect on the EEG and determine whether that effect might be thermally mediated. Thirty-six healthy adults participated in a randomized, double-blind, counterbalanced provocation study. A water-perfusion suit (34 C) was worn throughout the study to negate environmental influences and stabilize skin temperature. Participants attended the laboratory on four occasions, the first being a calibration session and the three subsequent ones being exposure sessions. During each exposure session, EEG and skin temperature (8 sites) were recorded continuously during a baseline phase, and then during a 30 min exposure to a 920 MHz GSM-like signal (Sham, Low RF-EMF (1 W/kg) and High RF-EMF (2 W/kg)). Consistent with previous research, alpha EEG activity increased during the High exposure condition compared to the Sham condition. As a measure of thermoregulatory activation, finger temperature was found to be higher during both exposure conditions compared to the Sham condition, indicating for the first time that the effect on the EEG is accompanied by thermoregulatory changes and suggesting that the effect of RF-EMF on the EEG is consistent with a thermal mechanism.

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Lukyanova, Svetlana N., N. I. Karpikova, Yu G. Grigoryev y I. A. Veselovskiy. "THE STUDY OF RESPONSES OF THE HUMAN BRAIN TO ELECTROMAGNETIC FIELD OF NON-THERMAL INTENSITY". Hygiene and sanitation 96, n.º 9 (27 de marzo de 2019): 848–54. http://dx.doi.org/10.18821/0016-9900-2017-96-9-848-854.

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This article is an array of materials of own research of the responses of the human brain to radio frequency electromagnetic fields (EMF RF) of non-thermal intensity. The results of studies with the participation of volunteers presented a characterization of the response of the central nervous system to short-term exposures to EMF RF from the industrial generator and various cellular communication standards under conditions with predominantly irradiation of the head. There was given an estimation of the physiological significance of these effects and their dependence on human EEG typological features. The examination of persons working in conditions of chronic exposure of EMF RF, allowed present the dependence of neural effects on the work experience.

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García-Minguillán López, Olga, Ana Jiménez Valbuena y Ceferino Maestú Unturbe. "Significant Cellular Viability Dependence on Time Exposition at ELF-EMF and RF-EMF In Vitro Studies". International Journal of Environmental Research and Public Health 16, n.º 12 (13 de junio de 2019): 2085. http://dx.doi.org/10.3390/ijerph16122085.

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The human concern about the effect of electromagnetic fields (EMFs) has changed over time from the effects produced by EMFs of extremely low frequencies (ELFs) to the effects produced by exposure to a radio frequency (RF), with concerns shifting toward EMFs due to the development of new technologies and forms of communication. Previous studies have analysed the effects produced at different frequencies without considering in detail the effect of the time of exposure. Therefore, in the present study, we analysed in vitro the effect produced by a 100 µT EMF at different ELFs and exposure times in glioblastomas, as well as the effect produced in a fibroblast by an RF-EMF of 2.54 GHz. Our results indicate a significant time dependence in cell viability of fibroblasts exposed to an RF-EMF of 2.54 GHz and a non-time-dependent effect in cell viability of glioblastomas exposed to an ELF-EMF, highlighting the possible relation between frequency and time of exposure.

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Petroulakis, Nikolaos, Mats-Olof Mattsson, Panos Chatziadam, Myrtill Simko, Andreas Gavrielides, Andrianos M. Yiorkas, Olga Zeni et al. "NextGEM: Next-Generation Integrated Sensing and Analytical System for Monitoring and Assessing Radiofrequency Electromagnetic Field Exposure and Health". International Journal of Environmental Research and Public Health 20, n.º 12 (8 de junio de 2023): 6085. http://dx.doi.org/10.3390/ijerph20126085.

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The evolution of emerging technologies that use Radio Frequency Electromagnetic Field (RF-EMF) has increased the interest of the scientific community and society regarding the possible adverse effects on human health and the environment. This article provides NextGEM’s vision to assure safety for EU citizens when employing existing and future EMF-based telecommunication technologies. This is accomplished by generating relevant knowledge that ascertains appropriate prevention and control/actuation actions regarding RF-EMF exposure in residential, public, and occupational settings. Fulfilling this vision, NextGEM commits to the need for a healthy living and working environment under safe RF-EMF exposure conditions that can be trusted by people and be in line with the regulations and laws developed by public authorities. NextGEM provides a framework for generating health-relevant scientific knowledge and data on new scenarios of exposure to RF-EMF in multiple frequency bands and developing and validating tools for evidence-based risk assessment. Finally, NextGEM’s Innovation and Knowledge Hub (NIKH) will offer a standardized way for European regulatory authorities and the scientific community to store and assess project outcomes and provide access to findable, accessible, interoperable, and reusable (FAIR) data.

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22

Meo, Sultan Ayoub, Mohammed Almahmoud, Qasem Alsultan, Nawaf Alotaibi, Ibrahim Alnajashi y Waseem M. Hajjar. "Mobile Phone Base Station Tower Settings Adjacent to School Buildings: Impact on Students’ Cognitive Health". American Journal of Men's Health 13, n.º 1 (7 de diciembre de 2018): 155798831881691. http://dx.doi.org/10.1177/1557988318816914.

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The use of mobile phones has remarkably increased and become a basic need of daily life. Increasing subscriptions of mobile phones boost the installation of mobile phone base station towers (MPBSTs) in crowded commercial and residential areas including near school buildings. This study investigated the impact of exposure to radiofrequency electromagnetic field (RF-EMF) radiation generated by MPBSTs on cognitive functions. Two hundred and seventeen volunteer male students aged between 13 and 16 registered from two different intermediate schools: 124 students were from School 1 and 93 students were from School 2. The MPBSTs were located within 200 m from the school buildings. In School 1, RF-EMF was 2.010 µW/cm2 with a frequency of 925 MHz and in School 2, RF-EMF was 10.021 µW/cm2 with a frequency of 925 MHz. Students were exposed to EMFR for 6 hr a day, 5 days a week for a total period of 2 years. The Narda Safety Test Solution device SRM-3006 was used to measure RF-EMF in both schools, and cognitive functions tasks were measured by the Cambridge Neuropsychological Test Automated Battery (CANTAB). Significant impairment in Motor Screening Task (MOT; p = .03) and Spatial Working Memory (SWM) task ( p = .04) was identified among the group of students who were exposed to high RF-EMF produced by MPBSTs. High exposure to RF-EMF produced by MPBSTs was associated with delayed fine and gross motor skills, spatial working memory, and attention in school adolescents compared to students who were exposed to low RF-EMF.

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Ishihara, Toru, Keiko Yamazaki, Atsuko Araki, Yuri Teraoka, Naomi Tamura, Takashi Hikage, Manabu Omiya, Masahiro Mizuta y Reiko Kishi. "Exposure to Radiofrequency Electromagnetic Field in the High-Frequency Band and Cognitive Function in Children and Adolescents: A Literature Review". International Journal of Environmental Research and Public Health 17, n.º 24 (8 de diciembre de 2020): 9179. http://dx.doi.org/10.3390/ijerph17249179.

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With increasing use of mobile phones, exposure to radiofrequency electromagnetic field (RF-EMF) in the high-frequency band associated with mobile phones has become a public concern, with potentially adverse effects on cognitive function in children and adolescents. However, findings regarding the relation of RF-EMF and cognitive function in children and adolescents have been inconsistent due to a number of study design-related factors, such as types of exposure and outcome measures, age of participants, and the era of study conduction. The present literature review focused on these possible factors that could explain this inconsistency. This review identified 12 eligible studies (participants ages 4 to 17 years) and extracted a total 477 relations. In total, 86% of the extracted relations were not statistically significant; in the remaining 14%, a negative relation between RF-EMF and cognitive performance was detected under limited conditions: when (1) RF-EMF was assessed using objective measurement not subjective measurement (i.e., questionnaire), (2) participants were relatively older (12 years and above) and had greater opportunity of exposure to RF-EMF, and (3) the collection of cognitive function data was conducted after 2012. Given that 86% of the extracted relations in this analysis were not statistically significant, the interpretation should be approached with caution due to the possibility of the 14% of significant relationships, extracted in this review, representing chance findings.

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24

Aerts, Sam, Kenneth Deprez, Leen Verloock, Robert G. Olsen, Luc Martens, Phung Tran y Wout Joseph. "RF-EMF Exposure near 5G NR Small Cells". Sensors 23, n.º 6 (15 de marzo de 2023): 3145. http://dx.doi.org/10.3390/s23063145.

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Of particular interest within fifth generation (5G) cellular networks are the typical levels of radiofrequency (RF) electromagnetic fields (EMFs) emitted by ‘small cells’, low-power base stations, which are installed such that both workers and members of the general public can come in close proximity with them. In this study, RF-EMF measurements were performed near two 5G New Radio (NR) base stations, one with an Advanced Antenna System (AAS) capable of beamforming and the other a traditional microcell. At various positions near the base stations, with distances ranging between 0.5 m and 100 m, both the worst-case and time-averaged field levels under maximized downlink traffic load were assessed. Moreover, from these measurements, estimates were made of the typical exposures for various cases involving users and non-users. Comparison to the maximum permissible exposure limits issued by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) resulted in maximum exposure ratios of 0.15 (occupational, at 0.5 m) and 0.68 (general public, at 1.3 m). The exposure of non-users was potentially much lower, depending on the activity of other users serviced by the base station and its beamforming capabilities: 5 to 30 times lower in the case of an AAS base station compared to barely lower to 30 times lower for a traditional antenna.

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Bodewein, Lambert, Dagmar Dechent, David Graefrath, Thomas Kraus, Tobias Krause y Sarah Driessen. "Systematic review of the physiological and health-related effects of radiofrequency electromagnetic field exposure from wireless communication devices on children and adolescents in experimental and epidemiological human studies". PLOS ONE 17, n.º 6 (1 de junio de 2022): e0268641. http://dx.doi.org/10.1371/journal.pone.0268641.

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Background For more than 20 years, the potential health risks of radiofrequency electromagnetic field (RF EMF) exposure from mobile communication devices on children and adolescents have been examined because they are considered sensitive population groups; however, it remains unclear whether such exposure poses any particular risk to them. Objectives The aim of this review was to systematically analyze and evaluate the physiological and health-related effects of RF EMF exposures from wireless communication devices (mobile phones, cordless phones, Bluetooth, etc.) on children and adolescents. Methods This review was prepared according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Methodological limitations in individual studies were assessed using the Office of Health Assessment and Translation (OHAT) Risk-of-Bias Rating Tool for Human and Animal Studies. Results A total of 42 epidemiological and 11 experimental studies were eligible for this review. Most of the studies displayed several methodological weaknesses that limited the internal validity of the results. Due to a lack of consistency regarding the outcomes as well as the lack of scientific rigor in most reviewed studies, the body of evidence for the effects of RF EMF of mobile communication devices on subjective symptoms, cognition, and behavior in children and adolescents was low to inadequate. Evidence from the studies investigating early childhood development, brain activity, cancer, and physiological parameters was considered inadequate for drawing conclusions about possible effects. Discussion Overall, the body of evidence allows no final conclusion on the question whether exposure to RF EMF from mobile communication devices poses a particular risk to children and adolescents. There has been rapid development in technologies generating RF EMF, which are extensively used by children and adolescents. Therefore, we strongly recommend high-quality systematic research on children and adolescents, since they are generally considered as sensitive age groups.

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Jeong, Ye, Yeonghoon Son, Na-Kyung Han, Hyung-Do Choi, Jeong-Ki Pack, Nam Kim, Yun-Sil Lee y Hae-June Lee. "Impact of Long-Term RF-EMF on Oxidative Stress and Neuroinflammation in Aging Brains of C57BL/6 Mice". International Journal of Molecular Sciences 19, n.º 7 (19 de julio de 2018): 2103. http://dx.doi.org/10.3390/ijms19072103.

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The expansion of mobile phone use has raised questions regarding the possible biological effects of radiofrequency electromagnetic field (RF-EMF) exposure on oxidative stress and brain inflammation. Despite accumulative exposure of humans to radiofrequency electromagnetic fields (RF-EMFs) from mobile phones, their long-term effects on oxidative stress and neuroinflammation in the aging brain have not been studied. In the present study, middle-aged C57BL/6 mice (aged 14 months) were exposed to 1950 MHz electromagnetic fields for 8 months (specific absorption rate (SAR) 5 W/kg, 2 h/day, 5 d/week). Compared with those in the young group, levels of protein (3-nitro-tyrosine) and lipid (4-hydroxy-2-nonenal) oxidative damage markers were significantly increased in the brains of aged mice. In addition, levels of markers for DNA damage (8-hydroxy-2′-deoxyguanosine, p53, p21, γH2AX, and Bax), apoptosis (cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase 1 (PARP-1)), astrocyte (GFAP), and microglia (Iba-1) were significantly elevated in the brains of aged mice. However, long-term RF-EMF exposure did not change the levels of oxidative stress, DNA damage, apoptosis, astrocyte, or microglia markers in the aged mouse brains. Moreover, long-term RF-EMF exposure did not alter locomotor activity in aged mice. Therefore, these findings indicate that long-term exposure to RF-EMF did not influence age-induced oxidative stress or neuroinflammation in C57BL/6 mice.

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Aerts, Sam, Günter Vermeeren, Matthias Van den Bossche, Reza Aminzadeh, Leen Verloock, Arno Thielens, Philip Leroux et al. "Lessons Learned from a Distributed RF-EMF Sensor Network". Sensors 22, n.º 5 (22 de febrero de 2022): 1715. http://dx.doi.org/10.3390/s22051715.

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In an increasingly wireless world, spatiotemporal monitoring of the exposure to environmental radiofrequency (RF) electromagnetic fields (EMF) is crucial to appease public uncertainty and anxiety about RF-EMF. However, although the advent of smart city infrastructures allows for dense networks of distributed sensors, the costs of accurate RF sensors remain high, and dedicated RF monitoring networks remain rare. This paper describes a comprehensive study comprising the design of a low-cost RF-EMF sensor node capable of monitoring four frequency bands used by wireless telecommunications with an unparalleled temporal resolution, its application in a small-scale distributed sensor network consisting of both fixed (on building façades) and mobile sensor nodes (on postal vans), and the subsequent analysis of over a year of data between January 2019 and May 2020, during which slightly less than 10 million samples were collected. From the fixed nodes’ results, the potential errors were determined that are induced when sampling at lower speeds (e.g., one sample per 15 min) and measuring for shorter periods of time (e.g., a few weeks), as well as an adequate resolution (30 min) for diurnal and weekly temporal profiles which sufficiently preserves short-term variations. Furthermore, based on the correlation between the sensors, an adequate density of 100 sensor nodes per km2 was deduced for future networks. Finally, the mobile sensor nodes were used to identify potential RF-EMF exposure hotspots in a previously unattainable area of more than 60 km2. In summary, through the analysis of a small number of RF-EMF sensor nodes (both fixed and mobile) in an urban area, this study offers invaluable insights applicable to future designs and deployments of distributed RF-EMF sensor networks.

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Frank, John William. "Electromagnetic fields, 5G and health: what about the precautionary principle?" Journal of Epidemiology and Community Health 75, n.º 6 (19 de enero de 2021): 562–66. http://dx.doi.org/10.1136/jech-2019-213595.

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New fifth generation (5G) telecommunications systems, now being rolled out globally, have become the subject of a fierce controversy. Some health protection agencies and their scientific advisory committees have concluded that there is no conclusive scientific evidence of harm. Several recent reviews by independent scientists, however, suggest that there is significant uncertainty on this question, with rapidly emerging evidence of potentially harmful biological effects from radio frequency electromagnetic field (RF-EMF) exposures, at the levels 5G roll-out will entail. This essay identifies four relevant sources of scientific uncertainty and concern: (1) lack of clarity about precisely what technology is included in 5G; (2) a rapidly accumulating body of laboratory studies documenting disruptive in vitro and in vivo effects of RF-EMFs—but one with many gaps in it; (3) an almost total lack (as yet) of high-quality epidemiological studies of adverse human health effects from 5G EMF exposure specifically, but rapidly emerging epidemiological evidence of such effects from past generations of RF-EMF exposure; (4) persistent allegations that some national telecommunications regulatory authorities do not base their RF-EMF safety policies on the latest science, related to unmanaged conflicts of interest. The author, an experienced epidemiologist, concludes that one cannot dismiss the growing health concerns about RF-EMFs, especially in an era when higher population levels of exposure are occurring widely, due to the spatially dense transmitters which 5G systems require. Based on the precautionary principle, the author echoes the calls of others for a moratorium on the further roll-out of 5G systems globally, pending more conclusive research on their safety.

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Qahtan Wali, S. "RF-EMF Measurement for 5G over C-band and mm-Wave frequency band: Exposure assessment and Procedures". IOP Conference Series: Materials Science and Engineering 1254, n.º 1 (1 de septiembre de 2022): 012002. http://dx.doi.org/10.1088/1757-899x/1254/1/012002.

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Abstract The 5G network is intended to accommodate a significant quantity of mobile data traffic as well as a great number of wireless connections. It improves cost, power consumption, and offers ultra-low latency and ultra-high dependability to enable new services in a variety of sectors. However, the general public is concerned about the possible health dangers linked with 5G equipment's Radio Frequency (RF) radiation, and numerous localities are actively lobbying to prevent 5G implementation. This aims to demonstrate the cause of increasing the amount of RF-EMF exposure, and the international standards of RF-EMF accepted limits. In addition, it aims to illustrate some measurement procedures to conduct RF-EMF measurement for different researchers and two other procedures and the result of the maximum exposure emitted by a 5G base station operating on 3.5 GHz and the mm-Wave frequency band by the author of this paper.

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Wang, Mengshuang, Mengni Zhu, Zhenjie Zhao, Xin Li y Jie Zhang. "A Novel and Versatile Microfluidic Device for Cell Assays under Radio Frequency Exposure". Biosensors 13, n.º 8 (27 de julio de 2023): 763. http://dx.doi.org/10.3390/bios13080763.

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Wound healing is a complex process composed of different stages, which involves extensive communication between the different cellular factors of the extracellular matrix (ECM). The radio frequency electromagnetic field (RF-EMF) has been used to accelerate the wound-healing process and it has been found to enhance cell alignment and mobility. The conventional methods for cell mobility analysis in an electromagnetic field generated by a radiation source are not advisable due to the low-precision, nonuniform distribution of the field, low efficiency of the analysis in batch and the lack of system integration for autonomous on-body operation. Here, a novel and versatile electromagnetic exposure system integrated with a microfluidic chip was fabricated to explore the EMF-induced response. A gradient electromagnetic field in a two-dimensional plane has been successfully established in the microchambers placed along the field line. In this work, by deploying our radiation experiments in vitro, we validated the on-chip monitoring of cell response to exposure. This electromagnetic field was simulated and human amniotic epithelial cells (HAECs) were cultured in different microchambers for continuous exposure to the electromagnetic field excited by a monopole RF antenna (1.8 GHz). New protrusions were generated and an obvious increase in filopodia with the increased field intensity was investigated. Meanwhile, the variation in intracellular Ca2+ concentration under the electromagnetic field was examined. The inhibitory effect of the Ca2+ circulation was further inspected to reveal the potential downstream signaling pathway in the RF-EMF-related bioassay, suggesting that cytoskeletal dynamics of cells under exposure are highly associated with the EGF receptor (EGFR)-cytoskeleton downstream signaling pathway. Finally, the field-induced cell elongation and alignment parallel to the field direction were observed. Additionally, the subsequent recovery (field withdrawal) and re-establishment (field re-exposure) were explored. These results indicated that this reliable and versatile exposure system for bioassay could achieve precise and high-throughput detection of the RF-EMF-induced cytoskeletal reorganization in vitro and evaluate the possible health risk from RF-EMF exposure.

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Yoon, Kyeonghee, Sojung Choi, Hyung-Do Choi, Nam Kim, Sang Bong Jeon, Kyung-Min Lim, Hae-June Lee y Yun-Sil Lee. "Effects of Radiofrequency Electromagnetic Fields and Ionizing Radiation on Amyloid Precursor Protein Processing and Cell Death". Journal of Electromagnetic Engineering and Science 20, n.º 4 (31 de octubre de 2020): 307–19. http://dx.doi.org/10.26866/jees.2020.20.4.307.

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The growing concerns regarding the adverse biological effects of radiofrequency electromagnetic fields (RF-EMFs), which are generated by common electronic devices, on the human brain led us to investigate their impact on Alzheimer’s disease (AD). We aimed to establish the effects of RF-EMF on the expression of molecular markers associated with amyloid precursor protein (APP), cell death, and clonogenic survival in HT22 and APP-overexpressing 7w-PSML cells. We compared the effects of RF-EMF at a high specific absorption rate (SAR) level with the neuronal-cell-death-inducing effects of ionizing radiation (IR). RF-EMF exposure (8 W/kg SAR) promoted the protein expression of ADAM10 (α-secretase) in the HT22 cells (p < 0.05) and downregulated the APP mRNA level in the 7w-PSML cells (p < 0.01). In contrast, IR (10 Gy) significantly reduced the APP and a disintegrin and metalloproteinase 10 (ADAM10) levels without altering their respective mRNA levels in these cells. Interestingly, IR exposure significantly upregulated BACE1 (α-secretase) at both the protein and mRNA levels, suggesting adverse effects in AD. IR induced cell death and reduced clonogenic survival in both cell lines. Although RF-EMF (high SAR level) influenced APP processing, it did not induce any deleterious change in either cell line. Thus, further studies are necessary to clarify the influence of RF-EMF on AD.

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Engiz, Begum Korunur. "Artificial Neural Network Based Prediction of Long-Term Electric Field Strength Level Emitted by 2G/3G/4G Base Station". Applied Sciences 13, n.º 19 (23 de septiembre de 2023): 10621. http://dx.doi.org/10.3390/app131910621.

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Accurate predictions of radio frequency electromagnetic field (RF-EMF) levels can help implement measures to reduce exposure and check regulatory compliance. Therefore, this study aims to predict the RF-EMF levels in the medium using an artificial neural network (ANN). The work was conducted at Ondokuz Mayis University, Kurupelit Campus, where the measurement location has line-of-sight to the base stations. Band selective measurements were also performed to assess the contribution of 2G/3G/4G services to the total RF-EMF level, which was found to be the highest among all services within the total band. Long-term RF-EMF measurements were carried out for 35 days within the frequencies of 100 kHz to 3 GHz. Then, an ANN model with Levenberg–Marquardt (LM) and Bayesian Regulation (BR) algorithms was proposed, which utilized inputs from real-time RF-EMF measurements. The performance of the models was assessed in terms of mean squared error (MSE) and regression performance. The average MSE and regression performances of the models were similar, with the lowest testing MSEs of 2.78 × 10−3 and 3.76 × 10−3 for LM and BR methods, respectively. The analysis of the models showed that the proposed models help to predict the RF-EMF level in the medium with up to 99% accuracy.

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Gryz, Krzysztof, Jolanta Karpowicz y Patryk Zradziński. "Complex Electromagnetic Issues Associated with the Use of Electric Vehicles in Urban Transportation". Sensors 22, n.º 5 (22 de febrero de 2022): 1719. http://dx.doi.org/10.3390/s22051719.

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The electromagnetic field (EMF) in electric vehicles (EVs) affects not only drivers, but also passengers (using EVs daily) and electronic devices inside. This article summarizes the measurement methods applicable in studies of complex EMF in EVs focused on the evaluation of characteristics of such exposure to EVs users and drivers, together with the results of investigations into the static magnetic field (SMF), the extremely low-frequency magnetic field (ELF) and radiofrequency (RF) EMF related to the use of the EVs in urban transportation. The investigated EMF components comply separately with limits provided by international labor law and guidelines regarding the evaluation of human short-term exposure; however other issues need attention—electromagnetic immunity of electronic devices and long-term human exposure. The strongest EMF was found in the vicinity of direct current (DC) charging installations—SMF up to 0.2 mT and ELF magnetic field up to 100 µT—and inside the EVs—up to 30 µT close to its internal electrical equipment. Exposure to RF EMF inside the EVs (up to a few V/m) was found and recognized to be emitted from outdoor radiocommunications systems, together with emissions from sources used inside vehicles, such as passenger mobile communication handsets and antennas of Wi-Fi routers.

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Schuermann, David y Meike Mevissen. "Manmade Electromagnetic Fields and Oxidative Stress—Biological Effects and Consequences for Health". International Journal of Molecular Sciences 22, n.º 7 (6 de abril de 2021): 3772. http://dx.doi.org/10.3390/ijms22073772.

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Concomitant with the ever-expanding use of electrical appliances and mobile communication systems, public and occupational exposure to electromagnetic fields (EMF) in the extremely-low-frequency and radiofrequency range has become a widely debated environmental risk factor for health. Radiofrequency (RF) EMF and extremely-low-frequency (ELF) MF have been classified as possibly carcinogenic to humans (Group 2B) by the International Agency for Research on Cancer (IARC). The production of reactive oxygen species (ROS), potentially leading to cellular or systemic oxidative stress, was frequently found to be influenced by EMF exposure in animals and cells. In this review, we summarize key experimental findings on oxidative stress related to EMF exposure from animal and cell studies of the last decade. The observations are discussed in the context of molecular mechanisms and functionalities relevant to health such as neurological function, genome stability, immune response, and reproduction. Most animal and many cell studies showed increased oxidative stress caused by RF-EMF and ELF-MF. In order to estimate the risk for human health by manmade exposure, experimental studies in humans and epidemiological studies need to be considered as well.

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Jimenez, Hugo, Minghui Wang, Jacquelyn W. Zimmerman, Michael J. Pennison, Sambad Sharma, Ivan Brezovich, Devin Absher et al. "Amplitude-modulated radiofrequency electromagnetic fields target hepatocellular carcinoma stem cells through activation of Cav 3.2 T-type calcium channels." Journal of Clinical Oncology 36, n.º 4_suppl (1 de febrero de 2018): 332. http://dx.doi.org/10.1200/jco.2018.36.4_suppl.332.

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332 Background: Amplitude-modulated 27.12 MHz radiofrequency electromagnetic fields (AM RF EMF) delivered via a spoon-shaped antenna placed on the patient’s tongue result in shrinkage of the primary and metastatic tumors in patients with advanced hepatocellular carcinoma (HCC). (Costa FP, et al. Br J Cancer. 2011;105:640-648.) The mechanism by which AM RF EMF have direct antiproliferative effect and disruption of the mitotic spindle on cancer cells is largely unknown. (Zimmerman JW, et al. Br J Cancer. 2012;106:307-313.) Methods: We assessed the Specific Absorption Rate (SAR) level and distribution inside the human body. In vitro experiments with HCC cells were performed as previously described (Zimmerman). Immunodeficient mice were subcutaneously implanted with Huh-7 HCC cells or patient-derived xenografts (PDX). Mice were exposed to HCC-specific AM RF EMF using systems replicating human exposure levels and treatment duration. Tumor samples were examined for EMT and cell cycle markers. Results: Intrabuccal delivery results in whole-body absorption of AM RF EMF. Proliferation of hepatitis B positive and negative cell lines as well as HCC cancer stem cells (CSCs) are blocked by AM RF EMF through Cav 3.2 T-type voltage gated calcium channels (VGCC). Proliferation of HCC is inhibited in vivo and tumor shrinkage occurs by dedifferentiation of HCC cells into quiescent myofibroblasts while the growth of intestinal and blood marrow cells is unaltered. Conclusions: Whole-body SAR ranges from 0.2 to 1 mW/kg and is significantly below the international safety limits for human exposure. Intrabucally-administered AM RF EMF is a novel targeted therapy for systemic treatment of advanced HCC with minimal off target effects. Inhibition of HCC CSCs may explain the extremely long term survival (>5 years) of several patients with advanced HCC.

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Regrain, Corentin, Julien Caudeville, René de Seze, Mohammed Guedda, Amirreza Chobineh, Philippe de Doncker, Luca Petrillo et al. "Design of an Integrated Platform for Mapping Residential Exposure to Rf-Emf Sources". International Journal of Environmental Research and Public Health 17, n.º 15 (24 de julio de 2020): 5339. http://dx.doi.org/10.3390/ijerph17155339.

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Nowadays, information and communication technologies (mobile phones, connected objects) strongly occupy our daily life. The increasing use of these technologies and the complexity of network infrastructures raise issues about radiofrequency electromagnetic fields (Rf-Emf) exposure. Most previous studies have assessed individual exposure to Rf-Emf, and the next level is to assess populational exposure. In our study, we designed a statistical tool for Rf-Emf populational exposure assessment and mapping. This tool integrates geographic databases and surrogate models to characterize spatiotemporal exposure from outdoor sources, indoor sources, and mobile phones. A case study was conducted on a 100 × 100 m grid covering the 14th district of Paris to illustrate the functionalities of the tool. Whole-body specific absorption rate (SAR) values are 2.7 times higher than those for the whole brain. The mapping of whole-body and whole-brain SAR values shows a dichotomy between built-up and non-built-up areas, with the former displaying higher values. Maximum SAR values do not exceed 3.5 and 3.9 mW/kg for the whole body and the whole brain, respectively, thus they are significantly below International Commission on Non-Ionizing Radiation Protection (ICNIRP) recommendations. Indoor sources are the main contributor to populational exposure, followed by outdoor sources and mobile phones, which generally represents less than 1% of total exposure.

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Romeo, Stefania, Olga Zeni, Maria Scarfì, Loredana Poeta, Maria Lioi y Anna Sannino. "Radiofrequency Electromagnetic Field Exposure and Apoptosis: A Scoping Review of In Vitro Studies on Mammalian Cells". International Journal of Molecular Sciences 23, n.º 4 (19 de febrero de 2022): 2322. http://dx.doi.org/10.3390/ijms23042322.

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In the last decades, experimental studies have been carried out to investigate the effects of radiofrequency (RF, 100 kHz–300 GHz) electromagnetic fields (EMF) exposure on the apoptotic process. As evidence-based critical evaluation of RF and apoptosis in vitro is lacking, we performed a scoping literature review with the aim of systematically mapping the research performed in this area and identifying gaps in knowledge. Eligible for inclusion were in vitro studies assessing apoptosis in mammalian cells exposed to RF-EMF, which met basic quality criteria (sham control, at least three independent experiments, appropriate dosimetry analysis and temperature monitoring). We conducted a systematic literature review and charted data in order to overview the main characteristics of included studies. From the 4362 papers retrieved with our search strategy, 121 were pertinent but, among them, only 42 met basic quality criteria. We pooled data with respect to exposure (frequency, exposure level and duration) and biological parameters (cell type, endpoint), and highlighted some qualitative trends with respect to the detection of significant effect of RF-EMF on the apoptotic process. We provided a qualitative picture of the evidence accumulated so far, and highlighted that the quality of experimental methodology still needs to be highly improved.

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Rathebe, Phoka C. "Exposure levels of radiofrequency electromagnetic fields from mobile base stations in Mpumalanga province, South Africa". Journal of Physics: Conference Series 2591, n.º 1 (1 de septiembre de 2023): 012035. http://dx.doi.org/10.1088/1742-6596/2591/1/012035.

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Abstract This study assessed the radiofrequency electromagnetic fields (RF-EMF) exposure levels proximal to primary school structures in the Mpumalanga province of South Africa. A calibrated Acoustimeter was used to measure the RF EMF levels at defined distance points of 50 and 100m away from the three mobile base stations, that provide a 4G network coverage. All the measurements were obtained from three mobile stations, each from one district municipality, using 30 minutes intervals for repeated measurements. The measured peak exposure level at 50m was 887 μW/m2 and 905 μW/m2 at 100m. No statistical difference was found when comparing the measurement data obtained at 50 and 100m from the three district municipalities. However, comparison of measurements obtained at 50 and 100m for all base stations were statistically significant, p-value< .002 and p< .003 respectively. The measured RF EMF exposure levels at both distance points were below the reference levels found under International Commission for Non-ionizing Radiation Protection (ICNIRP) RF guidelines. It is therefore essential for mobile base station companies to consider proximity of residential structures when installing new base stations in the future, and regularly maintain the components of mobile base towers, especially in the current state of power load shedding in South Africa.

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Toren, Murat y Nilgün Ulutaşdemir. "Evaluation of the Exposure of 4.5G Mobile Phone Base Stations in Different Band Radio Frequencies in Urban Center and Rural Areas in Turkey." Gümüşhane Üniversitesi Sağlık Bilimleri Dergisi 13, n.º 1 (27 de marzo de 2024): 66–73. http://dx.doi.org/10.37989/gumussagbil.1372777.

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Mobile phone base stations (MPBS) are electronic communication equipment, the number of which is rapidly increasing with the increasing need for mobile data use with developing technology. Since the middle of the 21st century, the effects of Radio Frequency Electromagnetic Fields (RF-EMF) emitted from base stations on human health have begun to be investigated. Although some of these studies have explained the harmful effects of RF-EMF on human health, others have stated that its effects on human health are limited and therefore contradictory results have emerged. RF-EMFs can have effects by transferring energy to human tissues, increasing temperature and changing the way cell membranes work. These effects may vary inversely with the proximity of MPBSs to residential areas and their safety distances. In this regard, rules such as location at least 300 m away from places with high population density (schools, hospitals, shopping malls, etc.) and at least 40 m above the ground are required. In this study, RF-EMF values of base stations installed both in Rize city center and rural areas in Turkey in different 4.5G frequency bands (GSM 900 DL- 1800 DL-2100 DL) were analyzed by real-time selective area analyzer (NARDA- It is measured using SRM 3006). The safety distances in the production/label values of these base stations, mathematically calculated EMF and measurement values were compared for different distances. Base station production/label and real-time measurement values of RF-EMF values emitted by MPBSs in urban centers and rural areas are determined and their effects on human health are evaluated.

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40

Jin, Hee, Kyuri Kim, Gayoung Park, Minjeong Kim, Haejune Lee, Sangbong Jeon, Juhwan Kim, Hakrim Kim, Kyungmin Lim y Yunsil Lee. "The Protective Effects of EMF-LTE against DNA Double-Strand Break Damage In Vitro and In Vivo". International Journal of Molecular Sciences 22, n.º 10 (12 de mayo de 2021): 5134. http://dx.doi.org/10.3390/ijms22105134.

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With the rapid growth of the wireless communication industry, humans are extensively exposed to electromagnetic fields (EMF) comprised of radiofrequency (RF). The skin is considered the primary target of EMFs given its outermost location. Recent evidence suggests that extremely low frequency (ELF)-EMF can improve the efficacy of DNA repair in human cell-lines. However, the effects of EMF-RF on DNA damage remain unknown. Here, we investigated the impact of EMF-long term evolution (LTE, 1.762 GHz, 8 W/kg) irradiation on DNA double-strand break (DSB) using the murine melanoma cell line B16 and the human keratinocyte cell line HaCaT. EMF-LTE exposure alone did not affect cell viability or induce apoptosis or necrosis. In addition, DNA DSB damage, as determined by the neutral comet assay, was not induced by EMF-LTE irradiation. Of note, EMF-LTE exposure can attenuate the DNA DSB damage induced by physical and chemical DNA damaging agents (such as ionizing radiation (IR, 10 Gy) in HaCaT and B16 cells and bleomycin (BLM, 3 μM) in HaCaT cells and a human melanoma cell line MNT-1), suggesting that EMF-LTE promotes the repair of DNA DSB damage. The protective effect of EMF-LTE against DNA damage was further confirmed by attenuation of the DNA damage marker γ-H2AX after exposure to EMF-LTE in HaCaT and B16 cells. Most importantly, irradiation of EMF-LTE (1.76 GHz, 6 W/kg, 8 h/day) on mice in vivo for 4 weeks reduced the γ-H2AX level in the skin tissue, further supporting the protective effects of EMF-LTE against DNA DSB damage. Furthermore, p53, the master tumor-suppressor gene, was commonly upregulated by EMF-LTE irradiation in B16 and HaCaT cells. This finding suggests that p53 plays a role in the protective effect of EMF-LTE against DNA DSBs. Collectively, these results demonstrated that EMF-LTE might have a protective effect against DNA DSB damage in the skin, although further studies are necessary to understand its impact on human health.

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Georgiou, Christos D., Electra Kalaitzopoulou, Marianna Skipitari, Polyxeni Papadea, Athina Varemmenou, Vassilios Gavriil, Evangelia Sarantopoulou, Zoe Kollia y Alkiviadis-Constantinos Cefalas. "Physical Differences between Man-Made and Cosmic Microwave Electromagnetic Radiation and Their Exposure Limits, and Radiofrequencies as Generators of Biotoxic Free Radicals". Radiation 2, n.º 4 (22 de septiembre de 2022): 285–302. http://dx.doi.org/10.3390/radiation2040022.

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The critical arguments for radiofrequency radiation exposure limits are currently based on the principle that radio frequencies (RF) and electromagnetic fields (EMFs) are non-ionising, and their exposure limits are even 100-fold lower than those emitted from the Sun in the whole RF-EMF spectrum. Nonetheless, this argument has been challenged by numerous experimental and theoretical studies on the diverse biological effects of RF-EMF at much lower power density (W/m2) levels than today’s exposing limits. On the other hand, less attention has been given to counterarguments based on the differences in the physics concepts underlying man-made versus natural electromagnetic radiation (EMR) and on the fact that man’s biology has been adapted to the natural EMR levels reaching Earth’s surface at single EMF wavelengths, which are the natural limits of man’s exposure to EMFs. The article highlights the main points of interaction of natural and man-made radiation with biomatter and reveals the physical theoretical background that explains the effects of man-made microwave radiation on biological matter. Moreover, the article extends its analysis on experimental quantum effects, establishing the “ionising-like” effects of man-made microwave radiation on biological matter.

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42

Aerts, Sam, Dirk Deschrijver, Luc Martens, Tom Dhaene y Wout Joseph. "Sequential measurement method to construct RF-EMF exposure maps". ISEE Conference Abstracts 2013, n.º 1 (19 de septiembre de 2013): 3088. http://dx.doi.org/10.1289/isee.2013.p-3-21-13.

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43

Chardon, Karen, Stéphane Delanaud, Pierre Tourneux y Erwan Stephan Blanchard. "How to Control Exposure to Fifth-Generation Radiofrequencies in Preterm Newborns in Incubator". Neonatology 120, n.º 5 (2023): 666–69. http://dx.doi.org/10.1159/000530658.

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Infant and family centered development care reduces infant distress and supports the parent and infant’s individual abilities. However, a new environmental factor is daily encountered: the radiofrequency electromagnetic fields (RF EMFs) with the most recent fifth-generation (5G) technology. Currently, the effects of RF EMF during development are discussed in animal models. The neonatal intensive care units are not spared from this stressor. The objective of this study was to evaluate the efficacy of a novel, electromagnetically insulating incubator cover to prevent the preterm infant from RF EMF exposure. A personal dosimeter was placed on the mattress of a closed incubator. Periods of exposure to low, medium, and high levels of 5G RF were delivered in the presence or absence of the incubator cover. The use of a silver-copper cover reduced the intensity of 5G radiofrequency levels from 52% to 57% (p < 0.0001), allowing to easily apply the precautionary principle.

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44

Pasche, Boris, Jacquelyn W. Zimmerman, Hugo Jimenez, Michael J. Pennison, Ivan Brezovich, Nengjun Yi, Niels Kuster, Frederico Costa y Alexandre Barbault. "Low levels of radiofrequency electromagnetic fields and cancer cell proliferation in vivo." Journal of Clinical Oncology 31, n.º 15_suppl (20 de mayo de 2013): e15049-e15049. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.e15049.

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e15049 Background: The incidence of hepatocellular carcinoma (HCC) is increasing but five-year survival remains dismal. Intrabuccal administration of amplitude-modulated radiofrequency electromagnetic fields (RF EMF) is a novel, non-invasive treatment modality resulting in whole body absorption of very low levels of RF EMF. Recent studies show that this approach elicits radiological responses in patients with HCC and breast cancer (J Exp Clin Cancer Res, 2009, 28:51; Br J Cancer, 2011, 105:640). Using an in vitro exposure system replicating the levels of exposure achieved in humans, we have shown that HCC cells and breast cancer cells are growth inhibited by HCC-specific and breast cancer-specific frequencies, respectively. Additionally, RF EMF exposure causes modulation of gene expression and disruption of the mitotic spindle (Br J Cancer 2012, 106:307). Methods: HCC cells were exposed to radiofrequency electromagnetic fields modulated at specific frequencies previously identified in HCC patients. MicroRNA arrays compared exposed and control groups of HCC cells. HCC cells were injected subcutaneously in NOD SCID mice. Following palpable tumor establishment, mice were exposed to HCC-specific RF EMF at a specific absorption rate of 0.4 W/kg and euthanized following excessive tumor burden. Results: We identified increased levels of miRNAs targeting proteins belonging to the PI3K pathway, specifically IP3/DAG signaling and intracellular calcium release, a pathway frequently disrupted in HCC and breast cancer. While HCC xenografts grew in control mice, we observed significant tumor shrinkage in mice exposed to HCC-specific modulation frequencies and residual xenograft tumor cells were infiltrated with fibrous tissue and showed significantly decreased proliferation and increased apoptosis. There was no evidence of altered cell proliferation or fibrosis in other organs. Conclusions: These findings are the first in vivo evidence of the efficacy of RF EMF in HCC and uncover a novel mechanism that targets cancer cell growth at specific modulation frequencies, by means of changes in PI3K signaling and release of intracellular calcium.

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45

Arslan, Badel, Nurcan Aras, Selma Yaman y Ulku Comelekoglu. "Investigation of genetic stress parameters in brain tissues of rats exposed to 1.8 GHz cell phone radiofrequency electromagnetic field". Medicine Science | International Medical Journal 13, n.º 1 (2024): 78. http://dx.doi.org/10.5455/medscience.2023.06.094.

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Heat Shock Proteins (HSPs) may induce various cellular processes, including replication, apoptosis, cell-cycle progression. Mitogen-activated protein kinase (MAPK) cascades are the primary mechanism that mediates the cellular stress response to extracellular stimuli and regulates transcriptional activity. It has been shown that mobile phone exposure can stimulate the Hsp27/p38MAPK stress pathway. In this study, twenty-seven mature female Wistar albino rats were exposed to 1.8 GHz radiofrequency electromagnetic field (RF-EMF) 2h/day for 8 weeks (SAR: 0.06 W/kg). Hsp27 and p38MAPK gene expressions were investigated in rat brains. Rats were divided into groups sham-exposed, cage control, and 1.8 GHz RF-EMF exposed. Hsp27 and p38MAPK gene expression levels were investigated from the brain. p38MAPK expression was found to be upregulated in RF-EMF exposed group (p=0.018) Hsp27 expressions were not altered (p=0.897). In conclusion, long-term exposure to 1.8 GHz cell phone radiation can activate the Hsp27/p38MAPK stress pathway. It may cause several cellular disorders and can affect brain function.

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46

Rubtsova, Nina B., Sergey Yu Perov y Olga V. Belaya. "Predictive model of biological equivalent radiofrequency electromagnetic field exposure assessment". Occupational Health and Industrial Ecology, n.º 12 (15 de febrero de 2019): 4–8. http://dx.doi.org/10.31089/1026-9428-2018-12-4-8.

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Introduction. The issues of radiofrequency electromagnetic field in near field human body exposure correct assessment and control methods improvement actualization determined the need to develop a predictive model that provides different exposure conditions in terms of their biological equivalence comparison.Materials and methods. The problem of laboratory rats and humans equivalent EMF exposure assessment in near and far fields was considered. It is proposed to use a set of criteria that include both the power absorption in the irradiated objects values and the exposure time, allowing to take into account the peculiarities of human body and animals species sensitivity to this factor to solve this problem.Results. Relations for RF EMF equivalent levels values calculation for concrete biological object in near and far fields are presented. There are presented the ratio to calculate EMF levels in terms of power density and energy exposure to case of human body exposure that is equivalent to experimental conditions of rats exposure.Discussion. The developed model can be used to compare the experimental conditions of exposure in the near field with PD values for far field (formed electromagnetic wave), which is most important for >300 MHz frequencies, as well as for the interpretation of EMF biological effects obtained in animal experiments to human exposure conditions assess. This provides a biologically based approach to control RF EMF intensity at any distance from the source and the comparison of the field strength levels with the PD values in the zone of the formed electromagnetic wave.Conclusion. The proposed model takes into account the physical patterns of energy absorption in different objects and differences of organisms species sensitivity to factor exposure; provides the ability to predict critical levels of irradiation for different human body organs and systems, taking into account the time of the factor exposure too.

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47

Celaya-Echarri, Mikel, Leyre Azpilicueta, Fidel Alejandro Rodríguez-Corbo, Peio Lopez-Iturri, Victoria Ramos, Mohammad Alibakhshikenari, Raed M. Shubair y Francisco Falcone. "Towards Environmental RF-EMF Assessment of mmWave High-Node Density Complex Heterogeneous Environments". Sensors 21, n.º 24 (16 de diciembre de 2021): 8419. http://dx.doi.org/10.3390/s21248419.

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The densification of multiple wireless communication systems that coexist nowadays, as well as the 5G new generation cellular systems advent towards the millimeter wave (mmWave) frequency range, give rise to complex context-aware scenarios with high-node density heterogeneous networks. In this work, a radiofrequency electromagnetic field (RF-EMF) exposure assessment from an empirical and modeling approach for a large, complex indoor setting with high node density and traffic is presented. For that purpose, an intensive and comprehensive in-depth RF-EMF E-field characterization study is provided in a public library study case, considering dense personal mobile communications (5G FR2 @28 GHz) and wireless 802.11ay (@60 GHz) data access services on the mmWave frequency range. By means of an enhanced in-house deterministic 3D ray launching (3D-RL) simulation tool for RF-EMF exposure assessment, different complex heterogenous scenarios of high complexity are assessed in realistic operation conditions, considering different user distributions and densities. The use of directive antennas and MIMO beamforming techniques, as well as all the corresponding features in terms of radio wave propagation, such as the body shielding effect, dispersive material properties of obstacles, the impact of the distribution of scatterers and the associated electromagnetic propagation phenomena, are considered for simulation. Discussion regarding the contribution and impact of the coexistence of multiple heterogeneous networks and services is presented, verifying compliance with the current established international regulation limits with exposure levels far below the aforementioned limits. Finally, the proposed simulation technique is validated with a complete empirical campaign of measurements, showing good agreement. In consequence, the obtained datasets and simulation estimations, along with the proposed RF-EMF simulation tool, could be a reference approach for the design, deployment and exposure assessment of the current and future wireless communication technologies on the mmWave spectrum, where massive high-node density heterogeneous networks are expected.

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Migdal, Pawel, Paweł Bieńkowski, Małgorzata Cebrat, Ewelina Berbeć, Mateusz Plotnik, Agnieszka Murawska, Przemysław Sobkiewicz, Agnieszka Łaszkiewicz y Krzysztof Latarowski. "Exposure to a 900 MHz electromagnetic field induces a response of the honey bee organism on the level of enzyme activity and the expression of stress-related genes". PLOS ONE 18, n.º 5 (12 de mayo de 2023): e0285522. http://dx.doi.org/10.1371/journal.pone.0285522.

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There are many artificial sources of radiofrequency electromagnetic field (RF-EMF) in the environment, with a value between 100 MHz and 6 GHz. The most frequently used signal is with a frequency of around 900 MHz. The direction of these changes positively impacts the quality of life, enabling easy communication from almost anywhere in the world. All living organisms in the world feel the effects of the electromagnetic field on them. The observations regarding the influence of a RF-EMF on honey bees, describing the general impact of RF-EMF on the colony and/or behavior of individual bees, such as reduction in the number of individuals in colonies, extended homing flight duration, decrease in breeding efficiency, changes in flight direction (movement of bees toward the areas affected by RF-EMF), increase in the intensity and frequency of sounds characteristic for those announcing the impending danger. In this work, we describe the changes in the levels of some of the stress-related markers in honey bees exposed to varying intensities and duration of RF-EMF. One-day-old honeybee worker bees were used for the study. The bees were randomly assigned to 9 experimental groups which were exposed to the following 900 MHz EMF intensities: 12 V/m, 28 V/m, and 61 V/m for 15 min, 1 h and 3 h. The control group was not exposed to the RF-EMF. Each experimental group consisted of 10 cages in which were 100 bees. Then, hemolymph was collected from the bees, in which the activity was assessed AST, ALT, ALP, GGTP, and level of nonenzymatic antioxidants albumin, creatinine, uric acid, and urea. Bees were also collected for the analysis of rps5, ppo, hsp10, hsp70, hsp90, and vitellogenin gene expression. Our study shows that exposure to a 900 MHz electromagnetic field induces a response in the honey bees that can be detected in the level of enzyme activity and the expression of stress-related genes. The response is similar to the one previously described as a result of exposition to UVB irradiation and most likely cannot be attributed to increased temperature.

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Vecsei, Zsuzsanna, Zsófia Szilágyi y György Thuróczy. "Radiofrequency personal exposimetry during outdoor entertainment of young adults: a case study". Radiation Protection Dosimetry 199, n.º 8-9 (24 de mayo de 2023): 865–71. http://dx.doi.org/10.1093/rpd/ncad087.

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Abstract Radiofrequency (RF) exposure has grown substantially over time in the public area. Personal dosimetry measurements are intended to estimate how human RF exposure relates to exposure limits that do not pose a health risk. For our case study, an outdoor festival was chosen to assess realistic RF exposure of young adults during their entertainment. Band-selective RF exposure—sorted along 2G–4G uplinks and downlinks, 5G and Wi-Fi bands—was evaluated. Electric field strength data subsets were classified on the basis of activities as well as crowd density. 2G contributed the most to the overall RF exposure. Highest RF exposure was associated with attendance in a concert. In moderately crowded situations, RF exposure was higher than in the most crowded ones. However, the total measured electric field values were higher than in other outdoor environment, but still far below the national and international directives of regulatory RF-EMF exposure limits.

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50

Khorseva, N. I. y P. E. Grigoriev. "Electromagnetic fields of cellular communication as a health risk factor for children and adolescents (review)". Health Risk Analysis, n.º 2 (junio de 2023): 186–93. http://dx.doi.org/10.21668/health.risk/2023.2.18.

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Modern telecommunication technologies rely on using radio-frequency electromagnetic field (RF EMF). They have brought many useful services into our life able to solve multiple issues. However, we should bear in mind that this exposure is open, uncontrollable and permanent. Given that, it seems relevant to investigate possible negative influence exerted by RF EMF on health of children and adolescents since this population group is the most vulnerable and sensitive to any external exposure. This review analyzes Russian and foreign studies with their focus on chronic influence of RF EMF created by cellular communication means on health of children (aged 6–10 years) and adolescents (aged 11–16 years). We have established several manifestations of health disorders in children and adolescents including asthenic syndrome (headache, irritability, increased fatigue, sleeping disorders, periodical pains in the heart and joints); mental deadaptation (anxiety, stress, depression, etc.); as well as their combinations. Along with all the aforementioned syndromes, effects produced by exposure to RF EMF become apparent through some indirect signs of memory and attention failure such as forgetfulness (inability to recall the necessary information in time) and inattention (inability to concentrate on an event or activity) and even through growing frequency of respiratory diseases. Basing on the analyzed studies by Russian and foreign researchers, we can conclude that they provide solid evidence of negative influence of electromagnetic fields created by cell phones on health of children and adolescents. Therefore, implementation of modern gadgets and their active use by children and adolescents should be accompanied with assessment of actual threats posed by them, health risk assessment, and development of scientifically substantiated standards for their safe use.

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